Stack-forming machine



June 13, 1967 1.. c. MERKLEY ETAL 3,324,989

STACK-FORMING MACHINE Filed June 7, 1965 6 Sheets-Sheet 1 INVENTOR.

Leo CMerZ'Zey Lea B. Hayes,

n 5 a @m M R e w June 13, 1967 Filed June 7, 1965 L.C.MERKLEY ETAL STACK-FORMING MACHINE 6 Sheets-Sheet 2 June 13, 1967 c. MERKLEY ETAL 3,324,989

STACK-FORMING MACHINE 6 Sheets-Sheet (5 Filed June 7, 1965 INVENTOR. Zea CflfrZ'ie Leo ziffalrese ATTORNEY June 13, 1967 L. c. MERKLEY ETAL 3,324,989

STACK-FORMING MACHINE Filed June 7, 1965 6 Sheets-Sheet 4 ATTOPyE'Y.

June 13, 1967 L. c. MERKLEY ETAL 3,

STACKFORMING MACHINE 6 Sheets-Sheet 5 Filed June '7, 1965 mmx 4TTORNEY.

June 13, 1967 c. MERKLEY ETAL 3,324,939

STACK-FORMING MACHINE 6 Sheets-Sheet 6 1 Filed June 1965 NNN more

I60 6%) way/rel? .S r. mwm K Na E WWW Wm fi m a v A 5 e M United States Patent 3,324,989 STACK-FORMING MACHINE Leo C. Merkley and Wayne R. Merkley, Mesa, and Leo B. Hakes, Phoenix, Ariz., and Irvin C. Simon, Kenmore, N.Y., assignors to National Gypsum Company, Buffalo,

N.Y., a corporation of Delaware Filed June 7, 1965, Ser. No. 461,641 18 Claims. (Cl. 19835) The present invention relates to a machine for stacking board-like members into stacks.

The present invention is particularly applicable to the stacking of gypsum laths which are shipped in stacks. Each lath has a face or preferred side and a back or unpreferred side. In use, the preferred sides face inwardly toward a room and the unpreferred sides abut the framing. Injury to the preferred side impairs proper functioning thereof in the sense that it does not receive plaster properly. Accordingly, it is desirable to form the stacks of laths with the unpreferred sides of the outer laths of each stack facing outwardly so that in the event these sides are damaged in transit, such damage will not impair the proper functioning of the preferred sides.

It is accordingly the object of the present invention to provide an improved machine for stacking board-like members, such as laths, into stacks with the unpreferred sides of the outer board-like members of each stack facing outwardly, to thereby eliminate the possibility of damage to the preferred sides during shipment of the stacks. It is a related object of the present invention to provide an improved stacking machine of the foregoing type which is capable of forming the stacks in a rapid and efficient manner. A further related object of the present invention is to provide a stacking machine which is relatively simple in construction. A further related object of the present invention is to provide a stacking machine which includes a simple arrangement for adjusting the machine to provide accurately formed stacks. Other objects and attendant advantages will readily be perceived hereafter.

The improved stacking machine of the present invention includes a magazine which receives the board-like members with their preferred sides facing downwardly. The magazine has slots on opposite sides thereof. A pusher bar reciprocates between the opposite sides to push a first group of board-like members through a first slot in one side of the magazine and thereafter reverses its movement to push a second group through a second slot in the opposite side of the magazine. The first group passes over a turnover bar and tilts downwardly. Conveyor belts invert the board-like members in the first group so that they assume a position with their unpreferred sides facing downwardly. A second conveyor thereafter moves the inverted members of the first group underneath the magazine in timed relationship to the movement of the pusher bar which pushes a second group, with the unpreferred sides of each member facing upwardly, onto the inverted first group, to thereby provide a stack wherein the lowermost board-like member has its unpreferred side facing outwardly and the uppermost member also has its unpreferred side facing outwardly. An arrangement is provided for varying the relative speeds of the pusher bar and the conveyor to effect alignment of the two groups of board-like members which are combined to form the stack. The present invention will be more fully understood when the following portions of the specification are read in conjunction with the accompanying drawings wherein:

FIGURE 1 is a schematic representation of a stack of gypsum laths with the outer laths of the stack having their back or unpreferred sides facing outwardly; FIGURE 2 3 ,324,989 Patented June 13, 1967 ice is a side elevational view of the improved machine for providing a stack such as shown in FIGURE 1, with certain portions of the machine omitted in the interest of clarity; FIGURE 3 is a plan view of the machine shown in FIGURE 2; FIGURE 4 is a view taken substantially along line 4-4 of FIGURE 3 with certain portions of FIGURE 3 omitted in the interest of clarity, FIGURE 4 indicating how a stack of laths is formed; FIGURE 5 is a view similar to FIGURE 4 but showing the manner in which a first group of laths is removed from the magazine and inverted for subsequently receiving a second noninverted group from the magazine, as shown in FIGURE 4; FIGURE 6 is a view taken substantially along line 66 of FIGURE 3, with certain parts omitted in the interest of clarity, and showing the manner in which the pusher bar is related to a portion of a magazine and the manner in which it is supported on rollens underneath the magazine; FIGURE 7 is a fragmentary schematic view showing the manner in which the pusher bar removes the laths which are to be subsequently inverted as shown in FIGURE 5; FIGURE 8 is a fragmentary schematic view showing the manner in which the pusher bar ejects a plurality of laths which are received on the group of inverted laths as shown in FIGURE 4; FIGURE 9 is a schematic view of an alternate drive arrangement for the machine; FIGURE 10 is a fragmentary cross sectional view taken through the hopper of an alternate embodiment of the present invention; FIGURE 11 is a fragmentary cross sectional vie-w taken substantially along line 11-11 of FIGURE 10 and showing the pusher bar moving to the left; FIGURE 12 is a fragmentary cross sectional view taken substantially along line l111 of FIGURE 10 and showing the pusher bar moving to the right; and FIGURE 13 is an electrical and pneumatic circuit diagram for indicating how the modified embodiment of FIGURES 10-12 operates.

In FIGURE 1 a stack 10 of laths which is formed by the improved machine of the present invention is shown. This stack 10 includes a plurality of laths 11 each having a preferred side or face 12 and an unpreferred side or back 13. Laths 11 are commonly called lath sheets or sheets of lath. However, to simplify the following description they will be called laths. As is well understood in the art, each gypsum lath 11 is filled with gypsum plaster and has suitable paper liner 14' forming the preferred side 12 thereof, the paper 14' being wound around the opposite edges 14 and terminating proximate said edges at 15. The back or unpreferred side of each lath 11 is covered by a suitable sheet of paper 16 which has its opposite edges overlying the edges of sheets 14 to provide a lapped joint which is glued.

In actual use the preferred sides or faces 12 face inwardly toward a room and the unpreferred sides 13 are in abutting relationship with the studding. The faces or preferred sides 12 receive plaster, the paper 14 which forms the faces being suitably treated for this purpose. It will readily be appreciated that the faces or preferred sides 12 do not have or should not have any break therein so that the plaster is received properly. Furthermore, thewet plaster never touches the lapper glued joints where the front and rear papers are secured and thus the moisture in the plaster cannot in any way affect the glued joints. Because damage to the preferred sides of the laths will impair the quality of the finished coat carried thereby, it is necessary to protect these preferred sides in transit, and to this end the stack shown in FIGURE 1 is formed with the unpreferred sides 13 of the outer laths 11 facing outwardly, the preferred sides 12 thus being protected against damage in transit.

While the ensuing description of the machine for forming the stack of laths shown in FIGURE 1 will be described specifically with respect to such laths, it will be appreciated that the improved machine of the present invention can be utilized to stack gypsum wall board and any other type of board-like members, such as plywood or the like having preferred and unpreferred sides.

The improved stacking machine 17 includes elongated horizontal frame sides 18 secured to each other by cross braces 19 and supported by pairs of legs 20, 21 and 22.

A magazine or hopper 23 is supported above members.

18 by inverted U-shaped brackets 24 having their upper central portions 25 secured to end plates 26 of magazine 23 by bolts 27 and their lower or leg portions 28 secured to frame members 18 by welding, bolts, or any other suitable means of attachment. In addition to end plates 26, magazine 23 includes sides 29 and 29'. Angle irons 30 mounted on the outer sides of plates 24 stabilize them against undesired deflection. Corner angles 31 secure sides 29 and 29 to plates 24 (FIGS. 3 and 4). It can readily be seen from FIGURE 4 that sides 29 and 29 converge downwardly. Bumper plates or ends 26 of the magazines are spaced from plates 24 by spacers 32 (FIG. 3), the length of which can be varied to vary the distance between plates 26 to permit the magazine to accommodate laths of different lengths. It will be appreciated that the sides of these laths are of approximately a size in plan to fit within the magazine bounded by sides 29 and 29' and ends 26. The laths 11 are received in magazine 23 with their preferred sides 12 facing downwardly, as they are conveyed from a preceding station.

The stacking machine 17 includes an arrangement for removing laths 11 from magazine 23 and forming stacks 11 shown in FIGURE 1. A platform 33 (FIG. 2) has its opposite ends mounted on channels 34 and 35. Channel 34 (FIG. 2) has its opposite ends secured to the lower ends of angles 36 (FIGS. 2 and 3), the upper ends of which are suitably secured to frame sides 18. Channel has its opposite ends secured to legs 22 (FIG. 2). Platform 33 mounts double-ended electric motor 37. Pulleys 38 of motor 37 are encircled by friction belts 39 which in turn encircle pulley 40 of gear reducer 41 which is also mounted on platform 33. The output sprocket 42 of gear reducer 41 is encircled by chain 43 which also encircles sprocket 44 keyed to shafft 45 having its opposite ends journalled in bearings 46 mounted on frame sides 18 (FIG. 3). Keyed to shaft 45 are spaced rollers 47, each of which is encircled by a conveyor belt 48 having a corrugated outer surface for carrying a stack of laths without slippage. Each belt 48 also encircles a roller 49 mounted on shaft 50, the opposite ends of which are journalled in bearings 51 secured to opposite legs 21 by plates 52. A belt tensioning roller 53 (FIGS. 3 and 4) is associated with each belt 48 and is journalled between arms 54, the opposite ends of which are pivotally mounted on pins 55 (FIG. 2) supported by angle 19 (FIGS. 2 and 3). It is the weight of rollers 53 which holds the belts 48 taut. The direction of rotation of motor 37 is such that the upper runs of belts 48 will move from left to right, or upwardly, in FIGURE 2.

Lath turning conveyor belts 556 are driven by rollers 57 which they encircle, rollers 57 being keyed to shaft 50 for rotation therewith. The outer portions of belt 56 are smooth to prevent marring of the laths which engage them abruptly, as will become more apparent hereafter. Belts 56 also encircle rollers 58 keyed to shaft 59, the opposite ends of which are journalled. in bearings 60 secured to the insides of frame sides 18 by plates 61. Plates 61 are adjustable on frame sides 18 to vary the tension of belts 56. It will readily be appreciated that since the upper runs of belts 48 move from left to right, the upper runs of belts 56 will also move from left to right. Stated another way, rollers 47, 49 and 58 will rotate in a clockwise direction in FIGS. 4 and 5.

The laths 11 are removed from magazine 23 by pusher bar 62 which is caused to reciprocate between positions proximate sides 29 and 29' of magazine 23. More specifically motor 37 has belts 63 mounted on pulley 64, said belts encircling pulleys 65 of a variable speed drive 66 which may be one known by the trade name P.I.V. which is made by the Link Belt Company and shown in their brochure Book 3074 on pages 2 and 3, said brochure having been copyrighted in 1961. The function of the variable speed drive 66 is to provide a variable speed output to shaft 67 which is driven from variable speed drive 66 and in turn is coupled to gear reducer 68 having an output sprocket 69 encircled by chain 70 which also encircles sprocket 71 keyed to shaft 72, the opposite ends of which are journalled in bearings 73 mounted on frame sides 18. Gear reducer 68 is mounted on platform 68' extending between legs 20. Keyed to the ends of shaft 72 are cranks 74 which in this instance are in the form of discs. Eccentrically and rotat-ably mounted on each of cranks 74 by pins 75 are first ends of links 76, the opposite ends of which are journalled at 77 (FIG. 3) to the opposite ends of pusher bar 62. Suitable turnbuckles are provided at the ends of links 76 for adjusting the length thereof. As can readily be visualized, links 76 always remain parallel to each other during rotation of cranks 74. As can be seen from FIGURES 3 and 6, links 76 lie outside of magazine 23 and slots 78 formed below edges 79 of plates 24 permit pusher bar 62 to move back and fourth as driven by links 76.

When links 76 have traveled as far to the right as they can, edge 80 (FIG. 8) of pusher bar 62 will lie to the right of the laths 11 in magazine 23 and the lowermost laths 11 will be supported on rollers 81 which are mounted on angles 82 which in turn are supported on channels 83 extending between frame sides 18. When pusher bar 62 is as far to the right in FIGURES 2, 3 and 4 as it can go, edge 80 is at least to the right of inside surface 84 of magazine side 29' (FIG. 8). Movement to the left of pusher bar 62 will cause edge 80 thereof to engage the right ends (FIG. 7) of twoof laths 11 and move them to the left in FIGURE 7 through slot 85 (FIG. 6) which is bounded by edges 86 and 87 of plate 29. It can readily be seen that edge 80 of pusher bar 62 is of slightly less height than the thickness of two laths 11 (FIG. 7) and therefore will only engage the edges 11' of two of said laths. It is also to be noted from FIGURE 3 that the rollers 81 of each group are staggered with respect to the rollers mounted on an adjacent angle 82 so as to cause the laths 11 to travel with a minimum of undulation.

During the movement to the left of pusher bar 62 in FIGURE 7, it is supported on rollers 81, as is the lowest lath 11. However, the undersides of the ends of pusher bar 62 ride on slideways 111 (FIG. 6) mounted on frame sides 18 when bar 62 moves beyond rollers 81. Furthermore as can be seen from FIGURES 7 and 6, an inclined cam surface 88 forms the upper portion of pusher bar 62 which consists of a substantially rectangular bar 62 and a wedge shaped bar 63' which is shorter than bar 62. The inclined surface 88 serves to support the remainder of laths 11 above pusher bar 62 traveling to the left, thereby minimizing the friction between the upper surface of the two laths 11 being removed from the magazine and the lowermost under surface of the lowest lath 11" being retained. In this respect it can be seen from FIGURE 7 that lath 11" has an edge 12'.

which abuts the lower portions of plate 29 immediately above lowermost edges 86 and also a part of plate 29 immediately above edge 87 (FIG. 6) to prevent movement to the left of lath 11" with lath 11.

The pusher bar 62 will continue to be driven to the left by crank 74 until such time as edge 89 thereof lies to the right of surface 90 of side plate 29. It is to be noted at this point that a notch 91 is provided in plate 29 and is bounded by edges 92 to permit surface 88 of pusher bar 62 to clear plate 29 while the portions adjacent edges 86 hold lath 11" and those above it from moving to the left with the laths being ejected to the left. After edge 89 of pusher bar 62 has moved to the right of surface 90 of plate 29, all of the laths including lath 11 and lath 11 above it will rest squarely on the surface of rollers 81.

The two laths which were removed through slot 85 will pass over turnover bar 93 having its opposite ends mounted on plates 94 secured to frame sides 18. Turnover bar 93 may be adjusted after the loosening of the screws 95 in slots 96 in plates 94 and may be retained in their adjusted positions by the subsequent retightening of said screws. After the right ends of laths 11 have cleared slot 85, they will tilt from position 97 of FIGURE to position 98 by pivoting in a counterclockwise direction about turnover bar 93. The lowermost edges of laths 11 will hit the downwardly moving upper runs of belts 56 and be caused to continue their counterclockwise movement toward the position shown by numeral 99. Because the central portion of the laths are held relatively stationary while their lowremost portions move to the right in FIGURE 5, a point will be reached when the central portion of the laths is to the left of the lowermost portion and the laths 11 will drop onto the upper runs of belts 56 and also rest on the upwardly moving upper runs of belts 48. As can be seen from FIGURE 5 the inverted laths 11 will then be caused to move underneath magazine 23 and toward plate 29' thereof.

While all of the foregoing turning action has been occurring to invert a pair of laths 11, pusher bar 62 will be caused to move to the right from a position wherein right edge 89 thereof was to the left of surface 90 (FIG. 7) of magazine side 29. Surface 89 of pusher bar 62, being larger than the thickness of two laths 11, but less than the thickness of three, will engage three of the laths and move them to the right as shown in FIGURE 8 through slot 100 located below the lowermost edge 101 of plate 29. The group of three laths 11 moving to the right with their preferred sides facing downwardly will be ejected from magazine 23 in timed relationship with the movement of a pair of inverted laths moving upwardly with belt 48 to assume the relationship shown in FIGURE 4. Thus two inverted laths 11 with their unpreferred sides facing downwardly will receive three laths 11 with their unpreferred sides facing upwardly to form a stack of five laths shown in FIGURE 1 wherein the outermost laths have their unpreferred sides 13 facing outwardly. Channels 102 are supported on channels 103 and 104 (FIG. 2), said channels 102 extending longitudinally of each of belts 43 to prevent the latter from sagging under the weight of the laths 11.

After pusher bar 62 has gone as far to the right as it can, the crank 74 will cause it to move to the left to repeat the above described step wherein two laths 11 are ejected through slot 85 below side 29 of the magazine. Thereafter pusher bar 62 will reverse its direction of movement and eject three laths 11 through slot 100 as described above. The foregoing action is continued as pusher bar 62 reciprocates back and forth. Thus stacks 10 of five laths are formed in an extremely rapid and efiicient manner.

It is to be noted at this point that the average speed of pusher bar 62 in travelling between its extreme right and extreme left positions is approximately equal to the average linear speed of conveyor belts 48. However, it can be seen that the distance traveled by pusher bar 62 from left to right in ejecting the three uppermost laths is less than the distance traveled by the group of laths which were inverted and travel upwardly on belts 48. In fact this ratio is approximately 1:2. Therefore it can be seen that the following action occurs. Assuming that pusher bar 62 is as far to the right as it can go it will then move to the left to eject two laths (FIG. 5). These laths will be inverted and start traveling upwardly on belts 48. In the meantime, pusher bar 62 will move to the right. However, it will eject three laths before the two which were ejected immediately previously can come into underlying relationship with the three now being ejected. Thereafter the pusher bar 62 will eject two laths again by moving to the left. However, after pusher bar 62 reverses its direction and moves to the right, the three laths ejected with this movement will drop onto the two laths which were initially ejected. In other words, since the laths which are inverted have to travel approximately twice as far as those which are laid on the top of the stack and since both the upper and lower groups travel at substantially the same average speed, each inverted group of laths receives the second noninverted group which is ejected thereafter, and not the first inverted group.

As noted above a variable speed drive 66 is provided for changing the speed at which pusher bar 62 reciprocates for the purpose of varying the alignment between the upper and lower groups of laths as they meet. In this respect if the average speed of the pusher bar is less than the linear speed of the belts 48, the three upper laths will tend to lag the two lower laths on which they must fall. Therefore by the use of the variable speed drive 66 the speed of the pusher bar may be increased to cause registry between the upper and lower groups of laths. Conversely, if the upper group tends to lead the lower group, the speed of the pusher bar may be slowed down by the use of variable speed drive 66 to cause its average linear speed to tend to equal the speed of belts 48. By the use of the above described adjusting mechanism accurate registry of the upper and lower groups can be obtained.

After the stack 10 has been formed in the above described manner, it will travel upwardly on belts 48 until such time as it reaches belts 103 encircling rollers 104 keyed to shaft 105 having its opposite ends journalled in bearings 106. Belts 103 also encircle rollers 107 which are journalled on shaft 45. At this point it is to be noted that shaft 105 is driven by chain 108 encircling sprocket 109 on shaft 105 and sprocket 110 on shaft 45, shaft 45 being driven as described above. Since there is a step down between sprockets 110 and 109, shaft 109 will travel faster than shaft 45 and therefore belts 103 will have a greater linear speed than belts 48. Therefore after the stack 10 moves onto belts 103 it will move away from the stacking portion of the machine at a more rapid rate than which the stacks move on belt 45.

In FIGURE 9 an alternate drive arrangement for machine 17 is shown which includes variable speed drive 66' driven from motor 37' by belt 63' encircling pulleys 64' and 65. Shaft 67 is a constant output shaft and there is no speed change between the input to variable speed drive 66 and the output realized at shaft 67'. Shaft 67 is coupled to shaft 67 leading to gear reducer 68 (FIG. 3). It can thus be seen that the pusher bars are driven at a speed which cannot be varied. However, variable speed drive 66' includes a variable output shaft 68' carrying pulley 69' which is encircled by belt 70' which in turn encircles pulley 40' of gear reducer 41 which is shown in FIGURE 3 and drives belt 48. By the adjusting of the output speed of shaft 68' the speed of belts 48 may be varied.

Essentially the drive of FIGURE 9 differs from the drive of the preceding figures in that it provides an arrangement for varying the speed of belts 48 while not providing for the varying of the speed of the pusher bar 62, whereas in the preceding figures the average speed of the pusher bar may be varied while the speed of belts 48 remains constant.

While the above description has been presented with respect to gypsum laths it will be understood that the instant stack forming machine has general utility in the forming of stacks of any type of board-like members.

In FIGURES 10-13 a modified embodiment of the present invention is shown. This embodiment differs from the preceding embodiment in that the pusher bar is actuated by pneumatic motors 121 which are actually piston and cylinder arrangements. This construction has the advantage that the machine will stop in the event that a lath becomes jammed and there will be no injury to the machine because of the inherent yieldability attainable with pneumatic motor arrangements. There are certain other differences from the embodiment shown in FIG- URES 19 and these will become apparent hereafter. However it is to be especially noted that the conveyor belt arrangement associated with magazine 122 may be identical to the corresponding structure shown in FIG- URES l-9 and this structure has therefore been omitted from FIGURES 10l3 in the interest of simplicity. In other words it is only the mechanism for removing the laths from the hopper which differs from the arrangement shown in FIGURES 1-9.

The laths 123 are placed in magazine 122 having opposite side walls 124 and 125 and end Walls 126 (FIG. 13). A limit switch 127 is mounted on side wall 124 and is actuated by laths 123 as they descend into the magazine. The switch 127 is associated with a time-delay relay so that as it is hit by each of the descending laths it will not close until such time as the laths have built up to a height in the magazine 122 which will keep switch 127 closed. Slots 128 and 129 are located underneath side walls 124 and 125, respectively, to permit the laths to be ejected from the magazine 122 in response to the reciprocation of pusher bar 120, as can be seen from FIGURES 11 and 12. While not shown, it will be understood that magazine 122 may be mounted on the machine in the same manner as the magazine of FIGURES 19 and the mounting structure has been omitted in FIGURES 1013 in the interest of simplicity. As can be seen from FIG- URES 11, 12 and 13 slots 128 and 129 are of the same size, and different numbers of laths 123 may be discharged from these slots by raising and lowering of the bed 130 as will become more apparent hereafter.

Pusher bar 120 extends across the width of the machine and ends 131 thereof ride on ways 132 which in turn are supported by frame members 133. As can be seen from FIGURE 10, the pusher bar 120 has spaced portions 134 which extend downwardly a greater amount than adjacent cut-away portions 135. Portions 134 rest on rollers 136 which are journalled on plates 137 extending upwardly from cross members 138. Brackets 139 are secured to ends 131 of the pusher bar and pins 140 extending from brackets 139 are secured to the ends 141 of piston shafts 142 (FIG. 13) which in turn are secured to pistons 143 located within cylinders 144, which in combination with pistons 143, form a pneumatic motor 121. The ends of cylinders 144 include brackets 145 for pivotally securing it to the frame of the machine.

The pusher bar is caused to reciprocate back and forth through slots 128 and 129 in the following manner: When pusher bar 120 is in the position shown in FIG- URE 13 it will cause normally open limit switch 145 to be closed. Furthermore when the machine is in operation master switch 146 will be closed. Whenever there are sufiicient laths 123 within magazine 122, normally open limit switch 127 will be closed and a circuit will be completed from L-1 to ground through leads 147, 148, 149, 150, now closed limit switch 127, lead 151, timer 152 and lead 153. Timer 152 is a device, conventional in the art, which will permit the foregoing circuit to be completed only when limit switch 127 has been closed for a sufficiently long period of time. In other words the mere momentary contact established by laths 123 passing limit switch 127 will not cause the foregoing circuit to be completed. It is only after there has been an established contact for a predetermined period of time, as when the magazine is full up to limit switch 127, that the foregoing circuit can be completed. Once timer 152 causes the foregoing circuit to be completed a circuit will be established from L-1 to ground through leads 147, 148 and 154, now closed contacts of timer 152, lead 155, closed master switch 146, lead 156, now closed limit switch 145 (which is held closed by pusher bar lead 157, relay coil 158 and lead 159. Upon energization of relay coil 158, armatures 160 and 161 will move upwardly into engagement with their respective contacts. Thus a circuit will be completed from L-l to ground through leads 147,148, 149, 162, 163, armature 160, lead 164, solenoid valve 165 and lead 166. When solenoid valve is thus actuated compressed air will be permitted to flow from a suitable source (not shown) through conduits 167 and 168, valve 165 and conduit 169 to chamber 170 behind piston 143 Within cylinders 144.

Valve 165 will also permit chamber 171 on the other side of piston 143 to be vented. Air is supplied to the other cylinder 144 by a parallel circuit (not shown). Thus pistons 143 will be moved to the left in FIGURE 13 and move pusher bar 120 to the left also. In so doing the left edge 172 of pusher bar 120 will engage two laths 123 (FIG. 11) and move them through slot 128. It will be appreciated that after pusher bar 120. loses contact with limit switch 145, the above described circuit through limit switch 145 will no longer be completed. However solenoid coil 158 is maintained in an energized condition by the completion of a circuit from L-l to ground through leads 147, 148, 149, 162, 173, now closed armature 161, lead 174, normally closed limit switch 175, lead 176, solenoid coil 158 and lead 159. Thus the above described circuit to solenoid valve 165 will be maintained in an energized condition notwithstanding the opening of limit switch 145, thereby causing the compressed air to be supplied to chamber 170 of cylinder 144 to cause pusher bar 120 to be moved to the left The foregoing movement of the pusher bar to the left is continued until it engages normally closed limit switch 175 and opens it, thereby disrupting the circuit to solenoid coil 158, which in turn causes arma-tures 160 and 161 to return to the position shown in FIGURE 13, thereby breaking the circuit to solenoid valve 165. When this occurs, an internal spring mechanism within the valve will cause it to shift so that compressed air will be supplied from the source through conduits 167, 168, valve 165 and conduit 177 to chamber 171 of cylinders 144 while permitting chambers 170 to be vented through conduits 169. This will cause pusher bar 120 to move to the right in FIGURE 13 and in so doing it will engage three laths 123 ('FIG. 12) and discharge them through slot 129. When pusher bar 120 again engages limit switch 145 it will close it and thus again establish the circuit through solenoid coil 158 to again cause motors 121 to drive pusher bar 120 to the left. The foregoing reciprocation of pusher bar 120 will continue until such time as the magazine 1 22 is emptied.

It is to be again noted that the two laths 123 which are pushed out through slot 128 will fall onto a belt such as 56 of FIGURE 2 and thereafter travel upwardly on a belt such as 48 until the laths underlie slot 129 whereupon the three laths 123 being discharged will fall onto the two underlying laths which have been inverted, to

thus provide a stack of laths, as explained in detail relative to FIGS. l-9.

'In order to discharge two laths when pusher bar 128 is moving -to the left and three laths when it is moving to the right, the bed 130 of the machine is in a raised position when the pusher bar 120 is moving to the left to thereby cause two laths to discharge through slot 128, and bed 130 is in a lowered position when pusher bar 120 is moving to the right to cause three laths to be discharged through slot 129. In order to raise and lower bed 130 the following occurs: When pusher bar 120 is in the position shown in FIGURE 13 it will be in engagement with normally open limit switch 178 to close the latter. Thus a circuit will be completed from L1 to ground through leads 147 and 179, closed master switch 180, leads 181 and 182, now closed limit switch 178, leads 183 and 184, solenoid coil 185 and lead 186. The solenoid coil 185 will thus be energized and armatures 187 and 188 thereof will move up into engagement with their associated contacts. Thus, a circuit will be completed from L1 to ground through leads 147 and 179, armature 180, leads 181, 189, armature 188, lead 190, solenoid valve 191 and lead 192. This will cause solenoid valve 191 to become energized to permit compressed air to flow from the compressed air source through conduits 167, 193, solenoid valve 191 and conduit 194 to chamber 195 of motor 196 to the left of piston 197 while permitting chamber 198 to be vented through conduit 199.

In addition a holding circuit will be established through solenoid coil 185 from L1 through leads 147, 179, armature 180, leads 181, 182, 200, normally closed limit switch 201, lead 202, armature 187, leads 203 and 184, solenoid coil 185 and lead 186 to ground. This will cause relay coil 1 85 to remain energized notwithstanding that pusher bar 120 has moved out of engagement with normally open limit switch 178.

When fluid pressure motor 196 is energized in the above described manner piston 197 will move to the right in FIGURE 13 and cause shaft 204 to move to the right with it. As can be seen from FIGURE 10, motor 196 has one end thereof pivotally secured to the frame of the machine at 205 and shaft 204 is pivotally secured to lever arm 206 at 207 (FIG. 10). Lever arm 206 in turn has its upper end 208 welded to rock shaft 209 which has its opposite ends journalled in a pair of spaced bearings 211 mounted on spaced cross members 138. Bearings 211 are oriented in a manner similar to bearings 220 (FIGS. 11 and 12). Spaced lever arms 213 (which are located on shaft 209 in a manner similar to lever arms 224 on shaft 223 in FIGS. 11 and 12) extend from rock shaft 209 and their outer ends are pivotally connected to brackets 214 by pins 215. Brackets 214 in turn are welded to cross members 216 which form part of bed 130. Spaced plates 217 extend upwardly from cross members 216 and pairs of adjacent spaced plates 217 journal rollers 218 (FIG. 10). Furthermore, a connecting rod 219 (FIG. 10) has one end pivotally connected to lever 206 at 220 and its other end pivotally connected to lever 221 at 222. The end of lever 221 remote from pivotal connection 222 is fixedly secured to rock shaft 223 which in turn has levers 224 (analogous to levers 213) extending therefrom and pivotally connected to brackets 225 by pins 226, said brackets 225 being connected to cross members 216. It can thus be seen that whenever motor shaft 204 is caused to move upwardly and to the right in FIGURE 10, levers 206 and 221 will pivot in a counterclockwise direction in unison to thereby rotate shafts 209 and 223, respectively. This will raise rollers 218 when pusher bar 120 is in engagement with limit switch 178 to thereby cause only two laths to be discharged from slots 128. It is to be noted at this time that the raising and lowering of rollers 218 may be effected because they fit within cutaways 135 in the pusher bar (FIG. 10).

After pusher bar 120 has completed its movement to the left in FIGURE 13 it will engage normally closed limit switch 201 and cause it to open, thereby breaking the circuit to solenoid coil 185 and deenergizing solenoid valve 191. A spring actuated mechanism within the valve will cause it to return to a position which permits compressed air to flow into chamber 198 of motor 196 and permits chamber 195 to be vented through valve 191. This will cause piston 197 to move shaft 204 downwardly and to the left in FIG. 10. In so doing it will cause levers 206 and 221 to pivot in a clockwise direction in FIGURE 10 and thus lower the bed 13 carrying rollers 218. \Vhen rollers 218 are thus lowered three l-aths 123 will be placed in alignment with slot 129 and pusher bar 120 will push three laths through slots 129 onto the two laths which were previously discharged from slots 128 and inverted by the mechanism shown in FIGURES 1-9.

If for any reason it is desired to make stacks of six laths rather than five it is only necessary to open switch armature 180 to thereby prevent limit switches 178 and 201 from operating and this will cause bed 130 to assume its lowermost position and thus only three laths will be discharged from slots 128 and 129 during reciprocation of pusher bar 120.

In the embodiment of FIGURES 10-13 the relative speeds of the conveyor belts and the pusher bar may be varied in any number of different ways. More specifically if the conveyor belt speed is maintained constant the air pressure supply to cylinders 144 may be increased or decreased to thereby speed up or slow down, respectively, the rate of pusher bar reciprocation. Furthermore, if the pressure supply to cylinders 144 is maintained constant, a conventional motor control arrangement may be utilized to vary the speed of the conveyor belts to thereby effect precise coinciding of the upper and lower series of laths which form the stacks.

While preferred embodiments of the present invention have been disclosed it will be appreciated that it is not limited thereto but may be otherwise embodied within the scope of the following claims.

We claim:

1. A machine for stacking a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a magazine for receiving a plurality of board-like members all facing in the same direction, said magazine including opposed first and second side members, first and second slots in said first and second side members, respectively, a pusher bar, motor means, linkage means operatively coupling said pusher bar to said motor means for causing said pusher bar to reciprocate between a position proximate the outside of said first side member to a position proximate the outside of said second side member and thereby alternately pass through said first and second slots to thereby cause at least one first board-like member to be ejected from said first slot and at least one second board-like member to be ejected from said second slot, means proximate said first slot for causing said first board-like member to tilt after being ejected from said magazine by said pusher bar and assume a position which is inverted with respect to the position which it assumed within said magazine, conveyor means for moving said inverted board-like member underneath said magazine in timed relationship to the movement of said pusher bar and causing said first inverted board-like member to pass under said second slot while said pusher bar ejects said second board-like member to thereby cause said second board-like member to fall with its preferred face facing the preferred face of said first board-like member and in superposed relationship therewith.

2. A machine for stacking a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a magazine for receiving a plurality of board-like members all facing in the same direction, said magazine including opposed first and second side members, first and second slots in said first and second side members, respectively, said first slot being of a width to permit a first group of said board-like members to pass therethrough and said second slot being of a greater width to permit a second group of said boardlike members to pass therethrough, said second group containing a larger number of board-like members than said first group, a pusher bar, motor means, linkage means operatively coupling said pusher bar to said motor means for causing said pusher bar to reciprocate between a position proximate the outside of said first side member to a position proximate the outside of said second side member and thereby cause said first group of board-like members to be ejected from said first slot and said second group of board-like members to be ejected from said second slot, means proximate said first slot for causing said first group of board-like members to tilt after being ejected from said magazine by said pusher bar and assurne a position which is inverted with respect to the position which said first group of board-like members assumed within said magazine, conveyor means for moving said first group of inverted board-like members underneath said magazine in timed relationship to the movement of said pusher bar and causing said first group of inverted board-like members to pass under said second slot while said pusher bar ejects said second group of board-like members to thereby cause said second group of board-like members to fall onto said inverted first group of board-like members with the preferred sides of said second group of board-like members facing the preferred sides of the first group of board-like members and in superposed relationship therewith to thereby provide said stack wherein the outer board-like members of said stack have their unpreferred sides facing outwardly and their preferred sides facing toward each other.

3. A machine for stacking a plurality of board-like members as set forth in claim 2 wherein the number of said board-like members in said second group exceeds the number of board-like members in said first group by a single board-like member and wherein said pusher bar includes first means for engaging the number of board-like members in said first group when moving toward said first slot from its position proximate said second slot and wherein said pusher bar includes second means for engaging the number of board-like members in said second group when moving toward said second slot from its position proximate said first slot.

4. A machine for stacking a plurality of board-like members as set forth in claim 3 wherein said pusher bar is of substantially elongated rectangular configuration and wherein said first means includes a first edge of said pusher bar and wherein said second means includes a second edge of said pusher bar, with said first edge being of less thickness than said second edge, and an inclined surface on top of said pusher bar joining the tops of said first and second edges, said inclined surface serving the function of tending to support the weight of said board-like members in said magazine when said pusher bar is moving toward said first slot.

5. A machine for stacking a plurality of board-like members as set forth in claim 4 wherein said first edge of said pusher bar is of a thickness which is slightly less than the thickness of said first group of board-like members and wherein said second edge of said pusher bar is of a thickness which is slightly less than the thickness of said second group of board-like members.

6. A machine for stacking a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a magazine for receiving a plurality of board-like members all facing in the same direction, means for ejecting a first number of board-like members from said magazine, means for inverting said first number of board-like members, means for ejecting a second number of board-like members from said magazine, and means for causing said second number to drop onto said inverted first number to thereby provide a stack wherein said unpreferred sides face outwardly and wherein said preferred sides face each other.

7. A machine as set forth in claim 6 wherein said means for inverting said first number comprises a turnover bar mounted proximate the area in which said first number is removed from said magazine, said turnover bar functioning to cause said first number to tilt after said first number passes over said bar.

8. A machine as set forth in claim 7 including a member for engaging said tilted first number and causing said tilted number to move in a direction opposite to the direction in which it moved during removal from said magazine while said first number is still in engagement with said turnover bar to thereby cause said first number to invert its position from that which it occupied in said magazine.

9. A machine as set forth in claim 8 including conveyor means for moving said inverted first number underneath said magazine, and means for causing said means for ejecting said second number to operate in timed relationship with the movement of said conveyor to cause said second number to be dropped from said magazine onto said inverted first number to thereby provide said stack.

10. A machine for stacking a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a frame, a magazine having first and second sides mounted on said frame for receiving a plurality of board-like members with their preferred sides facing downwardly, motor means, first and second conveyors, drive means coupling said motor means to said first and second conveyors, said conveyors each including endless belt means with the upper runs of each of said first and second conveyors moving in the same direction, crank arm means mounted on said frame, drive means for driving said crank arm means, a first slot in said first side of said magazine, a second slot in said second side of said magazine in opposition to said first slot, 21 pusher bar reciprocable between opposite sides of said magazine between a position proximate said first slot and a second position proximate said second slot, link means coupling said crank arm means to said pusher bar to effect said reciprocating movement, a turnover bar located externally of said magazine and proximate said first slot for causing a first number of board-like members to pass thereover when pushed through said first slot by said pusher bar traveling from a position proximate said second slot toward said first slot, said turnover bar tending to cause said first number of board-like members to tilt after they have completely passed through said first slot and are no longer supported by any portion of the magazine, said upper run of said first conveyor being inclined and traveling in a downward direction to cause the leading edge of said first number of board-like members to move downwardly and thus continue to pivot about said turnover bar until such time as said first number of board-like members turns over and assumes an inverted position, said upper run of said second conveyor being inclined and traveling upwardly and passing under said magazine to thereby carry said first number of inverted board-like members underneath and upwardly toward said magazine, said link means causing said pusher bar to move from a position proximate said first slot to a position proximate said second slot and in so doing move a second number of boardlike members out from said magazine through said second slot in timed relationship with the movement of said first number of board-like members to thereby cause said second number to drop on said first number whereby the lowermost board-like member of said first number is facing with its preferred side upwardly and its unpreferred side downwardly and whereby said uppermost board-like member of said second number is facing with its preferred side downwardly and its unpreferred side upwardly to thereby provide a stack of board-like members wherein the outermost board-like members have their preferred sides facing toward each other and their unpreferred sides facing outwardly.

11. A machine for stacking a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a frame, a magazine having first and second sides mounted on said frame for receiving a plurality of board-like members with their preferred sides facing downwardly, motor means, first and second conveyors, drive means coupling said motor means to said first and second conveyors, said conveyors each including endless belt means with the upper runs of each of said first and second conveyors moving in the same direction, crank arm means mounted on said frame, drive means for driving said crank arm means, a first slot in said first side of said magazine, a second slot in said second side of said magazine in opposition to said first slot, a pusher bar reciprocable between opposite sides of said magazine between a position proximate said first slot and a second position proximate said second slot, link means coupling said crank arm means to said pusher bar to effect said reciprocating movement, a turnover bar located externally of said magazine and proximate said first slot for causing a first number of board-like members to pass thereover when pushed through said first slot by said pusher bar traveling from a position proximate said second slot toward said first slot, said turnover bar tending to cause said first number of board-like members to tilt after they have completely passed through said first slot and are no longer supported by any portion of the magazine, said upper run of said first conveyor being inclined and traveling in a downward direction to cause the leading edge of said first number of board-like members to move downwardly and thus continue to pivot about said turnover bar until such time as said first number of board-like members turns over and assumes an inverted position, means for causing said inverted first number of board-like members to move onto said upper run of said second conveyor, said pusher bar while moving from a position proximate said first slot toward said second slot causing a second number of board-like members to move out from said magazine through said second slot in timed relationship with the movement of said first number of board-like members, and means for causing said second number to drop onto said first number whereby the lowermost boardlike member of said first number is facing with its preferred side upwardly and its unpreferred side downwardly and whereby said uppermost board-like member of said second number is facing with its preferred side downwardly and its unpreferred side upwardly to thereby provide a stack of board-like members wherein the outermost board-like members have their preferred sides facing toward each other and their unpreferred sides facing outwardly.

12. A machine for stacking a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a magazine for receiving a plurality of board-like members all facing in the same direction, means for ejecting a first number of board-like members from said magazine, means for inverting said first number of board-like members, means for ejecting a second number of board-like members from said magazine, means for causing said first and second numbers to move relative to each other to thus assume a superposed relationship to thereby provide a stack consisting of said first and said second numbers with the unpreferred sides of the outer board-like members facing outwardly, and means for varying the relative rate at which said first and said second numbers of board-like members move toward said superposed relationship to thereby insure accurate stacking of said first and said second numbers.

13, A machine for stacking -a plurality of board-like members each having a preferred and an unpreferred side with the resulting stack including outer board-like members with their preferred sides facing each other and their unpreferred sides exposed comprising a frame, a magazine for receiving a plurality of board-like members all facing in the same direction, said magazine including opposed first and second side members, first and second slots in said first and second side members, respectively, proximate the bottom of said magazine, said first slot being of a width to permit a second number of said board? like members to be ejected from said first slot and said being of a width to permit a second number of said boardlike members to pass therethrough, a pusher bar, motor means, linkage means operatively coupling said pusher bar to said motor means for causing said pusher bar to reciprocate below said magazine and between positions proximate the outside of said first and second side members and thereby alternately pass through said first and second slots to thereby cause said first number of boardlike members to be ejected from said first slot and said second number of board-like members to be ejected from said second slot, means proximate said first slot for causing said first number of board-like members to tilt after being ejected from said magazine by said pusher bar and assume a position which is inverted with respect to the position which said first group of board-like members assumed within said magazine, conveyor means for moving said first number of board-like members underneath said magazine toward said second slot while said pusher bar ejects said second number of board-like members to thereby cause said second number of board-like members to fall onto said inverted first number of board-like members with the uppermost board-like member of said second number having its unpreferred side facing upwardly and the lowermost board-like member of said first number having its unpreferred side facing downwardly, and means for varying the relative speeds of said pusher bar and said conveyor means to thereby cause said first and second number of board-like members to coincide and form a stack of substantially aligned boardlike members.

14. A machine for stacking a plurality of board-like members each having a first side and a second side opposite to said first side with the resulting stack including outer board-like members with their second sides facing each other and their first sides exposed comprising a magazine for receiving a plurality of stacked board-like members with their first sides facing upwardly and their second sides facing downwardly, said magazine including opposed first and second side members, first and second slots in said first and second side members respectively, a pusher bar, motor means coupled to said pusher bar for causing said pusher bar to reciprocate between positions proximate the outside of said first and second side members and thereby alternately pass through said first and second slots to thereby cause a first number of boardlike members to be ejected from said first slot and a second number of board-like members to be ejected from said second slot, means proximate said first slot for causing said first number of board-like members to be inverted after being ejected from said magazine by said pusher bar and assume a position with the second side of each of said board-like members facing upwardly and said first sides facing downwardly, conveyor means for moving said first number of board-like members below said magazine toward said second slot while said pusher bar ejects said second number of board-like members to thereby cause said second number of board-like members to fall onto said first inverted group of board-like members with the uppermost board-like member of said second number having its first side facing upwardly and the lowermost board-like member of said first number having its first side facing downwardly to thereby provide a stack with said first sides of said outer board-like members facing outwardly.

15. A machine as set forth in claim 14 wherein said pusher bar moves between said first and second positions at a first average speed and wherein said conveyor means moves at a second speed, and means for varying the relative speeds of said pusher bar and said conveyor means to thereby cause said first and second numbers of said board-like members to coincide and thus form a substantially aligned stack which includes said first and second numbers of board-like members.

16. A machine as set forth in claim 14 wherein said first slot is of a first size and said second slot is of a second size which is greater than said first size to thereby cause the number of board-like members which are 15 ejected from said first slot to be less than the number ejected from said second slot.

17. A machine for stacking a plurality of board-like members as set forth in claim 14 wherein said magazine includes a movable bed, means for moving said movable bed upwardly and downwardly in timed relationship with the reciprocation of said push bar to thereby cause said bed to assume a first higher elevation when said pusher bar moves from its position proximate said second slot toward a position proximate said first slot and to assume a lower elevation when said pusher bar moves from a position proximate said first slot toward said second slot to thereby effectively vary the size of said first slot relative to said second slot and cause less boardlike members to be ejected from said first slot than from said second slot.

means for varying the elevation of said bed comprise a pneumatic piston and cylinder arrangement.

References Cited UNITED STATES PATENTS 2,667,259 l/1954 Parker l98-33 2,967,630 1/1961 Parker 198-33 3,209,889 10/1965 Metzger 19833 GERALD M. FORLENZA, Primary Examiner.

J. E. OLDS, Assistant Examiner. 

10. A MACHINE FOR STACKING A PLURALITY OF BOARD-LIKE MEMBERS EACH HAVING A PREFERRED AND AN UNPREFERRED SIDE WITH THE RESULTING STACK INCLUDING OUTER BOARD-LIKE MEMBERS WITH THEIR PREFERRED SIDES FACING EACH OTHER AND THEIR UNPREFERRED SIDES EXPOSED COMPRISING A FRAME, A MAGAZINE HAVING FIRST AND SECOND SIDES MOUNTED ON SAID FRAME FOR RECEIVING A PLURALITY OF BOARD-LIKE MEMBERS THEIR PREFERRED SIDES FACING DOWWARDLY, MOTOR MEANS, FIRST AND SECOND CONVEYORS, DRIVE MEANS COUPLING SAID MOTOR MEANS TO SAID FIRST AND SECOND CONVEYORS, SAID CONVEYORS EACH INCLUDING ENDLESS BELT MEANS WITH THE UPPER RUNS OF EACH OF SAID FIRST AND SECOND CONVEYORS MOVING IN THE SAME DIRECTION, CRANK ARM MEANS MOUNTED ON SAID FRAME, DRIVE MEANS FOR DRIVING SAID CRANK ARM MEANS, A FIRST SLOT IN SAID FIRST SIDE OF SAID MAGAZINE, A SECOND SLOT IN SAID SECOND SIDE OF SAID MAGAZINE IN OPPOSITION TO SAID FIRST SLOT IN PUSHER BAR RECIPROCABLE BETWEEN OPPOSITE SIDES OF SAID MAGAZINE BETWEEN A POSITION PROXIMATE SAID FIRST SLOT AND A SECOND POSITION PROXIMATE SAID SECOND SLOT, LINK MEANS COUPLING SAID CRANK ARM MEANS TO SAID PUSHER BAR TO EFFECT SAID RECIPROCATING MOVEMENT, A TURNOVER BAR LOCATED EXTERNALLY OF SAID MAGAZINE AND PROXIMATE SAID FIRST SLOT FOR CAUSING A FIRST NUMBER OF BOARD-LIKE MEMBERS TO PASS THEREOVER WHEN PUSHED THROUGH SAID FIRST SLOT BY SAID PUSHER BAR TRAVELING FROM FROM A POSITION PROXIMATE SAID SECOND SLOT TOWARD SAID FIRST SLOT, SAID TURNOVER BAR TENDING TO CAUSE SAID FIRST NUMBER OF BOARD-LIKE MEMBERS TO TILT AFTER THEY HAVE COMPLETELY PASSED THROUGH SAID FIRST SLOT AND ARE NO LONGER SUPPORTED BY ANY PORTION OF THE MAGAZINE, SAID UPPER RUN OF SAID FIRST CONVEYOR BEING INCLINED AND 